I recently published libagentcrypt, a lightweight open source library for symmetric encryption using ssh-agent. The library relies on libsodium and also includes a small general purpose command line program that can encrypt and decrypt files or text using ssh keys, including those made available to a remote host through ssh agent forwarding. I am posting it here because I think it may be of interest to OpenWRT users.
The library is maintained on github at
The documentation is at https://ndilieto.github.io/libagentcrypt
The command line utility resembles gzip, except it encrypts/decrypts instead of compressing/decompressing. The man page is at